Seismic analysis of PWR 1300 MW reactor building

The seismic analysis of a PWR 1300 MW reactor building is complex. This structure is composed of two concrete cylindrical shells, tridimensional internals, equipments (vessel steam generator) and loops. In addition soil structure interaction must be taken into account. The present study deals with the influence of the modelisation on the seismic response of the whole structure. It is divided into three steps: 3D modelisation of the internals and calculation of an equivalent axisymmetric model for both horizontal and vertical seismic input; axisymmetric calculation of the reactor building: the equipment and loops being modelised as added mass, the soil as springs and dampers; 3D calculation using a substructure description of the problem. The seismic responses obtained by the two calculations are then compared. (orig.)